Genetic basis of nicotine withdrawal in a reduced complexity cross

项目摘要 尽管有证据表明基因对尼古丁依赖的病因有很大影响 (ND)，我们还远未确定个体易感性的具体遗传基础。 然后。这项建议的主要目标是确定新的遗传因素， 有助于尼古丁戒断，这是ND的一个重要方面，有助于复发 老鼠。我们观察到C57BL/6NJ有明显的尼古丁戒断特征差异 而在与之密切相关的C57BL/6J亚株中则不存在。因为亲本亚株 在基因上几乎相同，在实验中定位数量性状基因座(QTL) F2交叉(降低复杂性交叉；RCC)将极大地促进识别 导致戒断行为差异的新的遗传因素。在目标1中，我们将 使用RCC定位与以下基因相关的基因组区域或QTL 对多种尼古丁戒断措施的敏感度和恢复力。在目标2中，我们 将通过四个大脑的mna测序(rna-seq)进行转录组分析。 对照小鼠和慢性尼古丁处理小鼠的区域区域来自亲本雄性小鼠 女性C57BL/6J和C57BL/6NJ亚株。对照组小鼠的转录组将 在为未来的基因组编辑识别候选基因时充当有用的工具， 是差异表达的，是行为QTL的基础，以及提供 对影响易感性与韧性的神经元背景的基因组洞察 尼古丁戒断。基因差异表达的结果是 尼古丁将揭示与中枢神经可塑性相关的转录组的变化 以及支持ND的行为/更改。在目标3中，我们将验证候选人 数量性状基因和功能变异通过AIMS 1-2进行鉴定和排序。

Project Summary Despite evidence of strong genetic contributions to the etiology of nicotine dependence (ND), we are far from identifying the specific genetic bases of individual susceptibility to ND. The primary objective of this proposal is to identify novel genetic factors that contribute to nicotine withdrawal, an important aspect of ND that contribute relapse, in mice. We observed pronounced nicotine withdrawal traits differences in C57BL/6NJ strain but not in the closely related C57BL/6J substrain. Because the parental substrains are nearly genetically identical, quantitative trait locus (QTL) mapping in an experimental F2 cross (Reduced Complexity Cross; RCC) will greatly facilitate the identification of novel genetic factors that underlie differences in withdrawal behaviors. In Aim 1, we will use the RCC to map genomic regions, or QTLs, that are causally associated with susceptibility versus resilience to multiple measures of nicotine withdrawal. In Aim 2, we will conduct transcriptome analysis via mRNA sequencing (RNA-seq) of four brain regions regions in control mice and chronic nicotine-treated mice from the parental male and female C57BL/6J and C57BL/6NJ substrains. The transcriptome in control mice will serve as a useful tool both in identifying candidate genes for future genome editing that are differentially expressed and underlie the behavioral QTLs as well as providing genomic insight into the neuronal context that influences susceptibility versus resilience to nicotine withdrawal. Genes that are differentially expressed as a consequence of nicotine will reveal changes in the transcriptome relevant to central neuronal plasticity and the behaviors/changes that support ND. In Aim 3, we will validate candidate quantitative trait genes and functional variants identified and ranked by Aims 1-2.